How To Tell When Carpenter Ants Have Invaded

The signs of a carpenter ant infestation are often subtle; very subtle. Because so much of the damage that they do happens out of your line of sight, they can often leave a significant amount of damage in structures they occupy before the owner even becomes aware that there's a problem. 

Carpenter ants also have some natural behavior patterns that make them difficult to detect. They are mostly nocturnal, attacking while you're asleep. And because they prefer to feed on food outside of your home, you might never have the telltale warning signs of damaged food packages in your kitchen or pantry that other types of ants leave behind.

Carpenter ants often attack wood in hidden locations. Let's look at the problem a little closer:

If you're sitting on your deck and you see dozens of black ants crawling around, consider yourself a lucky homeowner. Carpenter ants prefer to be in shaded, moist areas. If you want to know whether or not your deck is being damaged by carpenter ants, you need to get under it (if you can). Examine the underside for frass (fine powder left behind as a result of carpenter ant tunneling) stuck to the wood of your deck or littered on the ground underneath. It may also be clinging to the side of your foundation wall.

Decks are a common target for carpenter ants, especially untreated, unstained, and unpainted decks that have been damaged by the sun. If you see signs of carpenter ants in this location, let it prompt you to contact a licensed professional and make sure those ants haven't gotten into your home.

On the inside of your home, there are a few places you can look for the frass created by carpenter ants:

• If you have a basement, you might find frass clinging to your soleplate, trusses, or concrete walls.
• Another great place to look is in your attic space. Carpenter ants commonly attack roof areas where wood has been compromised by rainwater. If you have a finished attic space, you're going to need to get into the voids to find this frass.
• Does your home have a crawlspace? If it does, it is a good idea to get into that space periodically and do a check for carpenter ant frass as well as termite shelter tubes. The darkness and moisture found in most crawlspaces make them ideal for pest activity and damage.